Maxima Function
triangularize (M)
Returns the upper triangular form of the matrix M,
as produced by Gaussian elimination.
The return value is the same as echelon,
except that the leading nonzero coefficient in each row is not normalized to 1.
lu_factor and cholesky are other functions which yield triangularized matrices.
(%i1) M: matrix ([3, 7, aa, bb], [-1, 8, 5, 2], [9, 2, 11, 4]); [ 3 7 aa bb ] [ ] (%o1) [ - 1 8 5 2 ] [ ] [ 9 2 11 4 ] (%i2) triangularize (M); [ - 1 8 5 2 ] [ ] (%o2) [ 0 - 74 - 56 - 22 ] [ ] [ 0 0 626 - 74 aa 238 - 74 bb ]